Knockout.js

4 days course (8h/day).
Notwithstanding the higher popularity of Angular.js and React.js ,
knowckout.js still maintains a good market share thanks to its interesting peculiarities:
it is based on an MVVM paradigm like Angular.js, so it is adequate for implementing modular complex applications,
but at the same time it is very simple to mix with server side templating.

It is the right choice when requirements include the support of legacy browsers, or
for building modular complex systems that mix client side and server side templating.